Over the past 30 days, people searching for information about Hillary Clinton on Google have been most likely to simply type in "hillary." Then, "clinton." Then, after some misspellings and some overlap with Donald Trump, people are most interested in learning about "hillary email" or "clinton email" or "hillary clinton email" or "hillary server." "Hillary email" even gets more searches than people looking for information about Clinton's duel with Bernie Sanders.

In her report on Clinton's decision this week to offer an apology for her use of a private e-mail system while secretary of state, the New York Times's Maggie Haberman explains the key moment: Clinton aides showed the candidate a video from a New Hampshire focus group, where participants said they wanted Clinton to address the topic.

"The focus group also showed that the e-mail issue was drowning out nearly everything else that Mrs. Clinton was hoping to communicate to voters," Haberman reported — "something Mrs. Clinton and her husband have complained about to friends."

The concern for Clinton and her team is how people react to ongoing questions about how and when the e-mail server was used. A recent poll from Quinnipiac University asked voters to describe Clinton in one word. The most common word chosen was "liar," followed by "dishonest" and "untrustworthy." The highest-ranking positive word was "experience" — which only half as many people said as "liar." (Nine people also said "murder," which is interesting.)

That goes hand-in-hand with Clinton's declining image numbers, though the correlation isn't totally clear. Among Democrats, she's still viewed favorably, but those numbers are slipping, too. Of more concern over the long term is Clinton's favorability with all voters, which in CNN/ORC polling has hit a low only seen once before, in March 2001 — long before the 2008 Democratic primary campaign.

So: Clinton apologized. It's fair to wonder the extent to which that will assuage broader concerns, given that Republicans will keep pressing the issue. But the move was clearly aimed at stanching discomfort among voters like those Democrats in New Hampshire.

And while apologies don't come easy from Clinton, they're nothing new on the presidential campaign trail. Clinton tiptoed around an apology in 2008 when she was caught embellishing a story about landing in Bosnia while first lady, but she offered a direct apology for loosely comparing Barack Obama's campaign to that of Robert Kennedy in 1968. She never apologized for her Iraq War vote during that cycle, saving that for her 2014 book, "Hard Choices."

That same year, she, Obama and John McCain all offered apologies to other campaigns for rude things said by staff and supporters. Obama apologized to Clinton for saying she was "likable enough" and to a reporter for calling the reporter "sweetie." McCain apologized to David Letterman for skipping his show.

In 2004, John Kerry apologized to John Edwards for making fun of his age (but didn't apologize for using a vulgarity when telling Rolling Stone he was amazed at how George W. Bush "f****d up" in Iraq). Howard Dean apologized for calling the Confederate flag "a painful symbol and reminder of racial injustice and slavery." Four years before that, Al Gore apologized for inaccuracies in comments he'd made on the trail, including the famous invented-the-Internet one. And Bush apologized for calling a Times reporter a "major-league a******" and for appearing at a university that banned interracial dating.

Apologies in political campaigns, in other words, are par for the course. But they're also largely sideshows, meant to tamp down outcry — real or feigned — from opponents and voters. Clinton's apology certainly won't muffle her critics, but she can worry about them next year.

For now, she'd just like to shift the tone on those Google searches and focus groups until she's got a few primaries under her belt.